Economic and clinical burden associated with respiratory viral infections after allogeneic hematopoietic cell transplant in the United States

Background Allogeneic hematopoietic cell transplant (allo-HCT) recipients are at increased risk for respiratory viral infections (RVIs), which invoke substantial morbidity and mortality. Limited effective antiviral options and drug resistance often hamper successful RVI treatment, creating additional burden for patients and the health care system. Methods Using an open-source health care claims database, we examined differences in clinical outcomes, health resource utilization, and total reimbursements during the 1-year period following allo-HCT in patients with and without any RVI infection (respiratory syncytial virus, influenza, parainfluenza virus, and human metapneumovirus). RVIs were diagnosed at any time <= 1 year after allo-HCT and identified by International Classification of Disease codes. Analyses were stratified by the presence or absence of acute or chronic graft-versus-host disease (GVHD). Results The study included 13 363 allo-HCT patients, 1368 (10.2%) of whom had a diagnostic code for any RVI. A higher proportion of patients with any RVI had pneumonia <= 1 year after allo-HCT compared to patients without any RVI, with or without GVHD. Patients with any RVI had higher all-cause mortality risk, longer length of post-allo-HCT hospital stay, higher readmission rate, and higher number of hospital days after allo-HCT compared to patients without the infection (all p < .05). Total unadjusted median reimbursements were higher for those with any RVI and each specific RVI assessed than those without the specific infection, with or without GVHD. Conclusion Allo-HCT patients with RVIs had significantly worse clinical outcomes and increased health resource utilization and reimbursements during the year following allo-HCT, with or without GVHD.